Justification:
This species is listed as Least Concern in view of its wide distribution, presumed large population, and because it is not declining at anything close to the rate required to qualify for listing in a threatened category.

Historically (1800s), muskoxen occurred from Point Barrow, Alaska (USA) east across Canada to northeast Greenland, south to northeast Manitoba (Canada), with the current range reduced (Grubb 2005). In the Canadian Arctic, muskoxen inhabit most large islands (except Baffin Island) and the mainland tundra of the Northwest Territories and Nunavut from the coast of Hudson Bay west to almost the Mackenzie River and south to the tree line in the Northwest Territories and western Nunavut. Muskoxen occur naturally over the entire Northeast and North Greenland west to Nyeboe Land. As well, there are several introduced populations, which are now well established in West Greenland and Qaannaaq. The species was re-introduced to Alaska (USA), and four locations in West Greenland (Denmark). Muskoxen were also introduced to Norway and Svalbard (Norway), although on Svalbard, they have since died out (Grubb 2005). The species occurred in Russia until around 2,000 years ago, and has been introduced to the Taimyr Peninsula and Wrangel Island.

In Canada, estimated muskox numbers in the Northwest Territories total 75,400 (1991-2005) of which 93% occur on the large arctic islands of Banks and western Victoria. Nunavut has an estimated 45,300 animals, of which 35,000 occur on the Arctic islands (unpublished data). A few muskoxen from the transplanted population on the Alaskan North Slope have strayed into Yukon. In northern Quebec (outside their natural range), Le Henaff and Crete (1989) counted 290 muskoxen in 1986.

In Alaska, 3,714 animals were estimated from aerial and ground counts between 2001 and 2005: Nunivak Island 609; Nelson Island 318; Seward Peninsula 2050; northwest Alaska 369; northeast Alaska 268. The re-established herds either fluctuate or are increasing in size and range, and in some areas, local people are concerned that they will compete with caribou and reindeer.

The population size in Greenland in 1991 was estimated to number 9,500-12,500. Of this total, Boertmann et al. (1992) recorded the following population estimates: 1,000 to 1,500 in North Greenland between Newman bight (82°N, 55’W) and Nioghalvfjerdfjorden (79°N); around 35 animals in the northern East Greenland region between 79°N and Jokelbugten (78°N); 450 to 550 between 78°N and Ardencable fjord (75°N); 2,900 to 4,600 in the areas between 75°N and Kong Oscar Fjord (72°N), and 4,600 to 5,000 the southernmost part of the species’ natural range in East Greenland, between 72°N and Scoresby Sund (70°N) (although recent unpublished surveys suggest that the population here has been reduced to approximately 4,000 animals (P. Aastrup pers. comm. to M. Forchhammer).

Muskoxen are large-bodied herbivores in an environment characterized by a short and variable plant growing season (when diet quality is high) and a long winter when the availability of low quality forage is highly variable through the snow cover. Typically, muskoxen live in mixed sex and age herds or small male bachelor herds which have home ranges within which muskoxen move between seasonal ranges. Although primarily grazers adapted to a diet of sedges and grasses, muskoxen also browse shrubs and forage selectively for forbs. They calve well before snow melt so lactation is supported by the cow’s fat reserves which the cow has to replenish during the brief summer. Muskoxen have a high threshold of fat reserves before conceiving which reflects their conservative breeding strategies. Winter ranges typically have shallow snow to reduce the energetic costs of digging through snow to reach forage. Muskoxen may also be susceptible to internal parasites but their role in muskox foraging ecology and population dynamics is unknown. The implications of the low genetic variability of muskoxen are likewise unknown.

Historically this species declined because of over-hunting, but population recovery has taken place following enforcement of hunting regulations. Management in the late 1900s was mostly conservative hunting quotas to foster recovery and recolonization from the historic declines. Currently, there is increasing realization that periodically on some arctic islands, die-offs of up to 40% of the island’s muskoxen occur when warmer fall weather leads to icing and deeper snow which restrict forage availability. On the North American mainland, typically muskoxen have expanded their range recolonizing historic ranges but behind the colonizing edge, abundance declines at least partially due to predation by wolves and grizzly bears. A persistent concern of people is that muskoxen through their presence (smell) and foraging are detrimental to caribou (Rangifer tarandus). The environmental consequences of climate warming is likely to have an impact on this species.

In Greenland, there are no major threats, although the fact that populations are often small in size and scattered, make them vulnerable to local or regional fluctuations in climate. Most populations are within the National Park, where they are protected from hunting. The portion of the population which is south of the National Park sustains a regulated quota harvest. Climate change in Northeast Greenland is expected to bring increased precipitation and milder winters, which might negatively affect the muskox population.

Unregulated commercial harvesting caused the disappearance of muskoxen from large areas of their Canadian continental ranges in the late 1880s and at the same time, ice storms probably reduced muskox numbers on Banks and western Victoria islands. After protection from hunting in 1917, muskoxen began to recover, and under the Northwest Territories and Nunavut Wildlife Act, are subject to aboriginal hunting limited by area-specific quotas and seasons. After 1980, the rights to hunt muskox could be transferred to non-aboriginal hunters for guided non-resident hunters and for commercial meat harvesting. In northern Canada, wildlife management is largely shifting from centralized government agencies to co-management boards and shared responsibility with aboriginal peoples. The wildlife management boards are developing management plans, and continue to regulate muskox hunting on the basis of sustainable yields. In the late 1990s, the annual quota for the NWT and Nunavut was 12,000 animals which includes 10,000 tags for Banks Island. The domestic harvest is relatively stable and while the commercial harvest for meat and hides (source of qiviut the fine underwool) annually varies, it averages about 1,000-2,000 muskoxen from Banks and Victoria islands. Management activities are mostly systematic aerial strip-transect surveys to track trends in population size, and as a basis for quota adjustments. No reserves are specifically set aside for muskoxen, but part of the rationale for establishing the Thelon Game Sanctuary was to protect a remnant muskox population from hunting. The species also occurs in three national parks: Quttinirpaaq (Ellesmere Island ), Aulavik (northern Banks Island) and Tuktu Nogait (Bluenose Lake, western Arctic mainland). In national parks, land use activities are controlled, but aboriginal hunting is permitted subject to conservation provisions. Conservation measures proposed for Canada: 1) Maintain sufficiently frequent population monitoring to track trends in abundance and distribution. 2) Utilize environmental screening of individual developments to protect muskox ranges outside any formally protected areas. 3) Public education is essentially as muskox have recolonized large areas and many people are unfamiliar with muskox ecology and behavior. People are often concerned about effects of muskoxen on caribou especially in areas muskoxen have recolonized.

In the United States, all five extant populations are the result of re-introductions of the muskox within and outside its historic range. The re-introductions began in 1935 with the translocation of animals, originally from northeast Greenland, to Nunivak Island. From 1967 to the most recent transplants in 1970, the Nunivak island population has been the source for all other Alaskan translocations (Klein 1988). Fully protected by law, muskox occurs in five protected areas and hunting is allowed under permit, with limited quotas on three of the five populations. Local subsistence hunting is given preference. Its status within the country is Not Threatened.

In Greenland, muskoxen occur in four protected areas, with indigenous populations in the vast Northeast Greenland National Park, and three introduced populations in Arnangarnup Qoorua Nature Reserve, and Kangerlussuag and Maniitsoq Caribou Reserves. Within these protected areas, muskox receives full protection. Most natural populations are within Northeast Greenland National Park. Outside protected areas, controlled hunting is allowed on Jameson Land in East Greenland, and near Kangerlussuaq in West Greenland. In both, quotas are determined annually and hunting is permitted only by full-time subsistence hunters. Between 1963 and 1991, muskoxen were translocated to three areas in the southwest previously uninhabited by muskox (near Kangerlussuaq, central West Greenland; Nunavik Peninsula, West Greenland; and Ivittuut, south Greenland), and a fourth population was reintroduced into former muskox range in Avanersuaq (Thule) in north-western North Greenland. Conservation measures proposed for Greenland: A proposal for development of a long-term management plan for existing muskox populations in West Greenland, is presently being considered by the Home Rule administration. A new system of game wardens in the West Greenland region, between Disko Bay (68°30’N) and Paamiut icecap (62°30’N), is being established to strengthen the enforcement of renewable resource legislation, and to control the performance of hunters in general.

Forchhammer, M.C. and Boertmann, D. 1993. The muskoxen, Ovibos moschatus, in north and northeast Greenland – population trends and the influence of abiotic parameters on population dynamics. Ecography 16: 299-308.